A Rare Case of Fetus in Fetu – The Lost Twin: A Case Report

Fetus in fetu is a rare congenital anomaly with an incidence of approximately 1 in 500000 live births. A 5-month-old pediatric patient presented with gross abdominal distension and respiratory distress. Contrast-enhanced CT of the abdomen revealed a well-encapsulated multiloculated solid-cystic lesion in the right retroperitoneum containing intralesional fatty components and calcifications forming appendiceal bones. Exploratory laparotomy was performed and the lesion was excised in toto. The patient remains under regular follow-up. Given the rarity of fetus in fetu we present this case to contribute to the literature and provide further insights into this unusual condition.